Sample command line call:
`GTK_DEBUG=interactive src/geeqie`
+### DEBUG_BT()
+
+Prints a backtrace.
+Use only for temporary debugging i.e. not in code in the repository
+
+```text
+When the LogWindow has focus, the F1 key executes the following action as a command line program:
+<options->log_window.action> <selected text>
+The log_window.action value must be set by editing the geeqierc.xml file manually.
+If no text is selected when the F1 key is pressed, the text either side of the cursor delimited by a space character or the beginning or end of the line is selected.
+This feature may be used to open an editor at a file location listed in the backtrace.
+```
+
+### DEBUG_FD()
+
+Prints a dump of the FileData hash list as a ref. count followed by the full path of the item.
+Use only for temporary debugging i.e. not in code in the repository
+
---
## GPL header
Use American, rather than British English, spelling. This will facilitate consistent
text searches. User text may be translated via the en_GB.po file.
+To avoid confusion between American and British date formats, use ISO format (YYYY-MM-DD) where possible.
+
To document the code use the following rules to allow extraction with Doxygen.
Not all comments have to be Doxygen comments.